Tides Today & Tomorrow in Roche Harbor, San Juan Island, WA

TIDE TIMES for Friday, July 31, 2026
The tide is currently rising in Roche Harbor, San Juan Island, WA.
Next low tide : 12:35 pm (-0.7 ft)
Next high tide : in 1h 30m at 5:34 am (6.5 ft)
Sunset today : 8:51 pm
Sunrise tomorrow : 5:46 am
Moon phase : Waning Gibbous (95% illuminated)
Tide Station Location : Station #9449834
Common Questions About Tides

Roche Harbor, San Juan Island, WA Tides - Aug 2085

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Wed4:376.67:42-0.77:466.85:488:49Waxing Gibbous1Wed
2Thu12:307.35:087.18:34-1.48:526.75:498:47Waxing Gibbous2Thu
3Fri1:317.45:377.49:24-1.99:466.45:518:46Waxing Gibbous3Fri
4Sat2:367.56:057.610:11-2.210:365.85:528:44Full Moon4Sat
5Sun3:427.56:347.810:56-2.211:265.05:538:43Full Moon5Sun
6Mon4:487.37:027.911:41-1.75:558:41Full Moon6Mon
7Tue5:537.17:328.112:174.012:25-0.95:568:40Waning Gibbous7Tue
8Wed6:596.78:028.11:113.01:090.35:588:38Waning Gibbous8Wed
9Thu8:086.28:348.02:072.01:541.75:598:36Waning Gibbous9Thu
10Fri9:265.89:077.93:041.12:423.16:008:35Third Quarter10Fri
11Sat11:015.69:437.64:020.53:354.46:028:33Third Quarter11Sat
12Sun12:525.85:010.14:405.56:038:31Third Quarter12Sun
13Mon2:276.36:04-0.16:086.26:048:29Third Quarter13Mon
14Tue3:356.87:07-0.27:546.46:068:28Waning Crescent14Tue
15Wed12:056.64:247.28:07-0.39:216.36:078:26Waning Crescent15Wed
16Thu1:096.45:037.49:00-0.310:106.06:098:24Waning Crescent16Thu
17Fri2:136.45:367.49:44-0.210:415.66:108:22Waning Crescent17Fri
18Sat3:126.46:037.410:23-0.111:085.26:118:20New Moon18Sat
19Sun4:046.46:257.310:570.211:364.66:138:18New Moon19Sun
20Mon4:516.46:417.211:300.56:148:16New Moon20Mon
21Tue5:376.36:557.212:074.012:021.06:168:15New Moon21Tue
22Wed6:246.27:137.312:393.412:351.66:178:13Waxing Crescent22Wed
23Thu7:136.17:357.31:142.71:082.46:188:11Waxing Crescent23Thu
24Fri8:055.98:007.21:512.11:423.26:208:09Waxing Crescent24Fri
25Sat9:035.88:287.12:301.52:184.16:218:07Waxing Crescent25Sat
26Sun10:135.78:577.03:141.02:564.96:238:05First Quarter26Sun
27Mon11:505.79:296.94:030.63:445.76:248:03First Quarter27Mon
28Tue1:506.04:580.24:556.36:258:01First Quarter28Tue
29Wed3:026.46:00-0.16:306.66:277:59First Quarter29Wed
30Thu3:446.87:05-0.57:506.46:287:57Waxing Gibbous30Thu
31Fri12:196.84:177.18:05-0.88:495.96:307:55Waxing Gibbous31Fri
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (9449834)

Common Questions About Roche Harbor, San Juan Island, WA Tides

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What time does the tide turn (slack tide) in Roche Harbor, San Juan Island, WA today?

Slack tide in Roche Harbor, San Juan Island, WA is approximately 9:04 am — midway between the next high and low tide, when tidal current is weakest. This is the preferred window for boat crossings, underwater visibility, and fishing in areas with strong currents.

Is this week a spring tide or neap tide in Roche Harbor, San Juan Island, WA?

Roche Harbor, San Juan Island, WA is currently in a spring phase. Tonight's moon is 95% illuminated. Spring tides (largest swings) occur near new and full moons; neap tides (smallest swings) occur near first and third quarter moons. Tidal ranges this week are near their weekly maximum.

What datum are Roche Harbor, San Juan Island, WA tide heights measured from?

Tide heights on this page are measured from Mean Lower Low Water (MLLW), the U.S. NOAA standard. A height of 0 ft represents the 19-year average of each day's lower low tide. Negative values indicate a "minus tide" — water levels below that long-term reference.

What factors can affect the tide predictions for Roche Harbor, San Juan Island, WA?

Tide predictions for Roche Harbor, San Juan Island, WA come from NOAA's harmonic analysis and are typically accurate within about ±10 minutes on timing and ±0.5 ft on height. Actual water levels can deviate further due to sustained winds, atmospheric pressure changes, river flow, and storm surge. During major weather events, be sure to check US Harbors weather pages for factors that could impact tidal predictions.

Which NOAA station provides tide data for Roche Harbor, San Juan Island, WA?

Tide data for Roche Harbor, San Juan Island, WA is sourced from NOAA Station #9449834. View the official NOAA station page at https://tidesandcurrents.noaa.gov/stationhome.html?id=9449834.

What is the moon phase in Roche Harbor, San Juan Island, WA tonight?

Tonight the moon over Roche Harbor, San Juan Island, WA is Waning Gibbous (95% illuminated). This places Roche Harbor, San Juan Island, WA in a spring tide cycle, so tidal ranges are near their weekly maximum this week.

US Harbors Tidal Data

The data in our tide charts, tide tables, and tide graphs is provided by NOAA and others. These predictions are derived mathematically from numerous inputs, including data from historical tide stations and nearby locations where sensors are actively recording. As shown in the tide graph at the top of this page, “Predicted” tides (blue) are what forecasting models expect to happen. “Observed” tides (red) are those recorded by local sensors in real time, overlaid on the predictions for direct comparison. We display Observed water levels for a select group of harbors including Portland, Maine, where a physical sensor monitors water levels in real time.

LEARN MORE ABOUT OUR TIDE DATA